Proximate composition and amino acid and mineral contents of Mormordica charantia L. pericarp and seeds at different maturity stages

The three maturity stages found in the pericarp and seeds of bitter melon (Momordica charantia) were investigated for their variations in proximate composition, amino acid profiles, and mineral contents. Moisture, starch, and total dietary fibre contents of pericarp, from all maturity stages (immature, mature and ripe), were significantly higher (P value <0.05) than those of ripe and mature seeds, while lipid and protein contents of seeds were statistically higher (P value <0.05) than those of pericarp. Maturity did not change the lipid content of the pericarp, while maturity progression decreased the protein content of bitter melon pericarp. A significant increase in the protein (30.4%) and lipid (37.6%) contents was observed in bitter melon seeds as the maturity progressed. Ripe seeds that have more than 30% protein could be a good protein source for functional ingredients in a food system. Bitter melon can be considered a good source of these nutrients.     

Simulated gastrointestinal digestion and in vitro colonic fermentation of date (Phoenix dactylifera L.) seed polyphenols

Date seeds are a by‐product of date fruit industry and a rich source of polyphenols. In this study, in vitro bioaccessibility and colonic fermentation of major polyphenols from date seed powder (DSP) and DSP‐fortified yoghurt (DSPY) were investigated using HPLC. Catechin, epicatechin and procyanidin A2, B1 and B2 were stable during simulated gastric and sequential intestinal digestion. Bioaccessibility was significantly (P < 0.05) higher for all compounds from DSPY compared with DSP. After in vitro colonic fermentation of insoluble digestion materials, most of the target compounds were metabolised by faecal bacteria to ferulic acid, 3‐hydroxyphenylacetic acid, 3‐phenylpropionic acid and 3‐(4‐hydroxyphenyl) propionic acid. DSPY contained significantly (P < 0.05) higher level of free polyphenols as indicated by higher bioaccessibility; however, the stability of the polyphenols and their fermentation products from DSPY were similar to that of DSP alone. These data would be useful in product developments incorporating DSP as a source of polyphenols in food products.     

Some chemical investigations of Amoora rohituka seed proteins

The inadequate supply of protein food, especially in the context of increasing population, has been an important factor in malnutrition in third world countries. Proteins were extracted from de-oiled seeds of Amoora rohituka, a potential source of non-conventional seed, in aqueous solutions of various pHs or by different concentrations of NaCl, KCl, CaCl₂ and MgSO₄ at pH 7.0. The nitrogen content of seeds and de-oiled seeds showed good protein content. Fractionation of protein was done to separate albumin, globulin, prolamine and glutelin. Gel-permeation chromatography on Sephadex G-200 revealed the presence of six components. PAGE identified different polypeptide bands in the range of 15.5–67.6 kDa in the total protein isolate (TPI) as well as in protein fractions. Amino acid analysis of TPI and fractions isolated identified 16 amino acids, most of which are essential. Studies on surface topographies of proteins and seed flour by scanning electron microscope are also incorporated.     

In vitro calcium bioaccessibility in raw and cooked cladodes of prickly pear cactus (Opuntia ficus-indica L. Miller)

The aim of this work was to determine the calcium bioaccessibility in Opuntia ficus indica L. Miller cultivars (Milpa Alta and Atlixco) and to evaluate the effect of cooking by using an in vitro digestion and dialysis method. The studied cladodes had a high content of calcium; however, only 16 and 9% of total calcium was dialyzable in Milpa Alta and Atlixco cultivars, respectively. The calcium dialyzability of Milpa Alta could be classified as medium level (10-19%) and Atlixco at the top of the rank assigned to low food dialyzability (<10%). Our results presented a significant negative correlation, between total oxalate and ionic dialyzable calcium (r = - 0.716, P ≤ 0.05). Milpa Alta could be a better source of calcium due to the higher bioaccessibility of ionic dialyzable calcium and lower total oxalate/calcium ratio. The cooking process did not affect significantly intestinal calcium bioaccessibility in any of the cultivars studied.     

Deterrent and insecticidal properties of bean seed (Phaseolus vulgaris L.) whole meal or protein extract incorporated into the diet of Callosobruchus maculatus (F.) (Coleoptera: Bruchidae)

Callosobruchus maculatus, a pest that causes serious damage to chickpea Cicer arietinum, cannot develop in the seeds of Phaseolus or Vigna spp. which contain lectins. The insecticidal activity towards C. maculatus in these seeds is attributed both to lectins with specific affinity to N-acetylglucosamine, the major component of insect chitin, and to alpha-amylase inhibitors (lectin-like proteins). The insecticidal properties of bean meal or bean protein extracts from different sources towards different pest species are variable and need to be experimentally evaluated. The main objective of this study was to determine through a feeding trial on artificial chickpea seed the potential of bean seed meal from a wild bean Vigna caracalla, four varieties of Phaseolus vulgaris, and of a protein extract of P. vulgaris seed, to alter different life history traits of C. maculatus. The chickpea weevil was set up on artificial chickpea seeds containing different amounts of bean meal to observe the effects on female oviposition, percentage of development to adulthood and juvenile development time. These traits were combined in a composite index measuring the alteration of the multiplication rate of C. maculatus fed on artificial seed. The activity of lectin-like extracts was observed on chickpea artificial seed spiked with bean seed extract. Incorporation of bean flour at a rate of 10 and 20% in chickpea artificial seed significantly decreased C. maculatus female fecundity, percentage of adult emergence, and greatly increased the development time. Feeding trials with protein extracts of P. vulgaris reduced fecundity and survival of C. maculatus. Incorporation of 10% V. caracalla bean seed meal in chickpea artificial seed, reduced the multiplication potential of C. maculatus by over 90% showing that bean seed lectin extracts are worthy of further investigation for post-harvest infestation control.     

Oil composition,mineral nutrient and fatty acid distribution in the lipid classes of underutilized oils of Trilepisium madagascariense and Antiaris africana from Nigeria

Trilepisium madagascariense (TM) and Antiaris africana (AA) are two underutilized plants from Nigeria. They have been subjected to standard analytical techniques in order to evaluate the proximate composition, physico-chemical properties, mineral nutrient, fatty acid composition and distribution in the lipid classes of the seeds and seed oils. The carbohydrate composition of these seeds are high; TM is 62.73 ± 0.30% and AA is 53.97 ± 0.50%. Iodine value of TM was found to be 46.10 ± 0.70 mg iodine/g while that of AA was 88.24 ± 0.50 mg iodine/g. The mineral composition of the seeds and the oils varied with K having the highest concentration in the seed and Na the highest concentration in the oils. Linoleic acid is the dominant fatty acid in the oil of AA with the highest composition in the neutral lipids while palmitic acid is the dominant fatty acid in oil of TM. Vitamin E, Gamma-Sitosterol, α and β-Amyrin, Lupeol, Stigmast-4-en-3-one, and hydrocarbons were isolated from these oils. The results of the proximate, mineral nutrient compositions, chemical characterization and fatty acid distribution of these seeds and seed oils shows their possibility as potential resources.     

Effect of high hydrostatic pressure on antioxidant capacity, mineral and starch bioaccessibility of a non conventional food: Prosopis chilensis seed

The aim of this work was to assess the influence of high hydrostatic pressure on antioxidant capacity, mineral and starch bioaccessibility of a non conventional food: “algarrobo” Prosopis chilensis seed. The algarrobo seed was pressurized at 500 MPa during 2, 4, 8 and 10 min. The antioxidant activity, mineral and starch content and bioaccessibility of algarrobo samples were significantly affected by the processing and digestion conditions. All treatments increased the bioaccessibility of the antioxidant activity (IC₅₀), minerals (dialysis and solubility) and starch (resistant and digestible) compared to the untreated sample. Bioaccessibility of calcium, iron and zinc in the treated sample for 500 MPA at 10 min, expressed as percentage solubility, was several-fold higher (three, three and five times, respectively) than in the untreated sample. Similar effect was observed in IC₅₀ value, algarrobo seed untreated sample exhibited the lowest antioxidant activity (0.11 ± 0.005 mg/ml), and followed by all treated samples (500 MPa at 2, 4, 8 and 10 min) which showed the strongest activity.In summary, the antioxidant capacity, mineral and starch content of the seed may be underestimated in the literature because the extraction solvents usually used do not allow a complete release of antioxidant compounds and, additionally, non-extractable polyphenols with a high antioxidant capacity are ignored. This correspondingly applies to the starch and mineral content. On the other hand, the analysis of in vitro digestive enzymatic extracts suggests that the antioxidant activity, minerals and starch of seed in the human gut may be higher than what might be expected from literature data based on measurements of aqueous-organic extracts.     

Efficacy of ozone for Callosobruchus maculatus and Callosobruchus chinensis control in cowpea seeds and its impact on seed quality

The insecticidal efficacy of ozone was evaluated against the adults of Callosobruchus maculatus (F.) and C. chinensis L. on stored cowpea seeds under laboratory conditions. Ozone was assessed at concentrations of 0.25, 0.5, 1.0, 1.5, and 2.0 g/m³. The effect of ozone treatments on the adult mortality after 1, 3, 5 and 7 days of treatment, progeny production after 45 days, cowpea seed weight loss, seed germination and chemical constituents of cowpea seeds were determined. Adult mortality of C. maculatus and C. chinensis was improved with the increase in ozone concentration. Thus, all tested concentrations caused complete adult mortality of C. chinensis after 7 days of treatment, while the concentrations of 1.0, 1.5, and 2.0 g/m³ caused complete adult mortality of C. maculatus after the same periods. Progeny of both species was significantly decreased in all ozone concentrations after 45 days of treatment. Nevertheless, strong suppression in progeny production was achieved at the highest concentration of ozone (2.0 g/m³). Also, the ozone treatment at the highest concentration protected the cowpea seeds from damage caused by C. maculatus and C. chinensis for 45 days. In addition, there was no significant effect of ozone treatments on the cowpea seed germination compared with untreated seeds. Moreover, the chemical analysis of treated cowpea seeds showed a slight decrease in protein, fat, carbohydrate, moisture, total phenolics, total flavonoids and tannins contents, and a slight increase in fiber and ash contents compared with untreated cowpea seeds. Our findings suggest the ozone can be effectively used for the control C. maculatus and C. chinensis and can provide sufficient protection of stored cowpea seeds.     

Influence of different organic solvents on the functional and sensory properties of lupin (Lupinus angustifolius L.) proteins

Protein isolates from lupin seeds are promising food ingredients due to their techno-functional properties. De-oiling of the lupin seeds is necessary to produce storable protein isolates. To assess the effects of different solvent extractions, functional and sensory properties of lupin flakes and derived protein isolates were studied. After de-oiling with acetone, n-hexane, 2-methyl pentane, diethyl ether, and 2-propanol, protein solubilities of the flakes ranging between 75% and 87% were similar to full-fat flakes (82%). Increased protein denaturation upon de-oiling with ethanol resulted in decreased solubility (64%) and thus protein recovery upon isolation. Nonetheless, all protein isolates had similar high solubilities (>90%) and emulsifying capacities varying from 710 to 760 mL g⁻¹. Comparing the flavour profile, the protein isolates obtained from ethanol and 2-propanol de-oiled flakes had significantly less “legume-like” flavour. In general, de-oiling lead to protein isolates with improved sensory profiles, thus good consumer acceptance, besides unchanged high functionality.     

Chemical characterization of Chinese chive seed (Allium tuberosum Rottl.)

Chinese chive seeds (Allium tuberosum Rottl.) (grown in China) were investigated. Density, thousand-grain weight, and hectolitre weight of seeds were 1.27 g/cm³, 4.9 g, and 71 kg/100 l, respectively. The results showed that Chinese chive seeds contained high amounts of oil (15.8%), dietary fibre (18.2%) and crude protein (12.3%). Oil of seeds was composed of 10.1% saturated and 90.0% unsaturated fatty acids. Linoleic(69.1%) and palmitic (7.0%) were the most abundant unsaturated and saturated fatty acids, respectively. Chinese chive seeds contained 4.5 mg/kg of thiamin, 2.8 mg/kg of riboflavin and 55.1 mg/kg of niacin. The mineral contents of the seed of A. tuberosum, for iron, calcium and zinc, were 580 mg/kg, 1328 and 80.8 mg/kg, respectively. Analysis of the amino acid content of Chinese chive seed revealed that it was a rich source of the essential amino acids, isoleucine, tryptophan and lysine. The study revealed that Chinese chive seeds had high levels of nutritionally important components, such as oil, minerals and essential amino acids.     

Chemical composition and potential of some underutilized tropical biomass. I: fluted pumpkin (telfairia occidentalis)

The seeds of Telfairia occidentalis have been subjected to standard chemical analysis to evaluate their properties. Proximate analysis indicated a low moisture content (6.30 ± 0.50%). The ash content was slightly higher than the range recommended for compounding of animal feed (3.44 ± 0.06%). The carbohydrate content was low (16.5 ± 0.12%). Starch, however, constituted the dominant carbohydrate (62.5 ± 0.48), while three sugars, glucose, fructose and sucrose were detected in the seed. The crude protein in the seed was high (16.0 ± 0.03%), a value which compared favourably with high protein seeds and nuts. In all, 16 amino acids were detected in the protein. Glutamic acid showed the highest concentration (16.4 g 100 g⁻¹), while lysine showed the lowest (2.6 g 100 g⁻¹). The brown oil extracted from the seed (yield 48.6 ± 0.94) had the following physicochemical properties; acid value, 3.05 ± 0.80 g, saponification value 166 ± 1.34 mg/KOH g⁻¹, free fatty acids, 0.3 g and peroxide value 3.02 ± 0.07 mg Eq kg⁻¹. The iodine value (80.1 ± 0.10)g 100 g⁻¹ indicated a preponderance of unsaturated fatty acid. Four fatty acids were detected whilst unsaturated acids constituted 61.3 g. Triglyceride was the dominant lipid species while hydrocarbons, waxes, sterols and sterol esters and higher alcohols, were detected in the unsaponifable matter. Results of nutritionally valuable mineral elements indicated that potassium occurred at the highest concentration.     

Amino acid profile and protein bioaccessibility of two Galdieria sulphuraria strains cultivated autotrophically and mixotrophically in pilot-scale photobioreactors

Galdieria sulphuraria is considered one of the most promising microalgae for food applications. In this study, we compared two strains of G. sulphuraria cultivated autotrophically and mixotrophically over 35 days in pilot-scale photobioreactors under nonsterile conditions. The low pH (<1.9) used for cultivation successfully prevented microbial contamination. The two strains had similar autotrophic and mixotrophic biomass productivities, the latter being 2.3 times higher than autotrophic productivity. Comparing the two strains, G. sulphuraria SAG 108.79 and ACUF 064 had 51% and 64% (w/w) protein and 4% and 9% (w/w) C-phycocyanin content, respectively. Interestingly, G. sulphuraria SAG 108.79 showed a protein bioaccessibility of 62%, in line with other microalgal species, whereas G. sulphuraria ACUF 064 had a protein bioaccessibility of only 14%. No differences in the amino acid profile were found between the two strains or between trophic modes. Stable and well-balanced protein profiles are encouraging results for future applications of this species.Industrial relevanceThe main focus of this study was the production of single-cell proteins using two strains of the polyextremophilic microalgae Galdieria sulphuraria. The acidic cultivation condition was sufficient to guarantee axenic production in not sterile conditions, even in the presence of glucose. Both strains were rich in proteins with a similar amino acid profile rich in all of the essential amino acids. Interestingly, there was a 4.4-fold difference in protein bioaccessibility between the two strains. Simple production of axenic microalgal biomass rich in protein is an encouraging result for future food applications of this species.     

Chemical investigation of Erythrina variegata Linn. seed proteins

Proteins were extracted from deoiled seeds of Erythrina variegata Linn., a potential source of non-conventional seed, in aqueous solutions of various pHs or by different concentrations of NaCl, KCl, CaCl₂ and MgSO₄ at pH 7.0. Nitrogen contents of the seeds and deoiled seeds showed good protein content. Fractionation of protein was done to separate albumin, globulin, prolamine and glutelin. Amino acid analysis of the total protein isolates (TPI) and the fractions isolated (except prolamine) identified 17 amino acids, most of which were essential. The molecular weights of TPI and the fractions were determined by SDS–PAGE electrophoresis. The results showed that TPI was composed of twelve bands, eight for globulin, nine for prolamine and six for glutelin. Studies on surface structure of the proteins and seed flour by scanning electron microscopy (SEM) are also included.     

Identification,biochemical characterization and biological role of defense proteins from common bean genotypes seeds in response to Callosobruchus maculatus infestation

Common bean is a legume of significant socioeconomic importance and is cultivated worldwide. This crop is affected by several pests and diseases, which cause considerable economic losses and reduce yield. In recent years, several studies have demonstrated the role of proteins and peptides with activity against a wide range of insects and pathogens. The objective of this work was to identify defense proteins, such as antimicrobial peptides, protease and amylases inhibitors in common bean genotypes and evaluate the relationship of these proteins with Phaseolus vulgaris seed resistance to Callosobruchus maculatus infestation. Nineteen common bean genotypes were subjected to protein extraction, pH 5.4, and precipitation with ammonium sulfate at 70% saturation. The obtained extracts were separated by tricine gel electrophoresis. Experiments were carried out with natural seeds of common beans and artificial seeds (Vigna unguiculata seeds covered with seed coats of common beans) to evaluate the rate of oviposition and development of the insect species Callosobruchus maculatus. Lipid-transfer proteins were identified in nine genotypes whereas defensins were present in all genotypes. The inhibitory activity of α-amylases and trypsin and fungal development were determined in crude extracts (50 μg mL⁻¹). The results also indicated that the extracts from all bean genotypes inhibited the activity of human salivary α-amylase and C. maculatus larval α-amylase. Except for the extracts of four genotypes, all other extracts inhibited trypsin activity. None of the extracts from the evaluated bean genotypes inhibited the growth of tested fungi. Natural seeds from all genotypes did not inhibit insect oviposition, however, the larvae did not survive after feeding on these seeds. Artificial seeds containing seed coat flour of all genotypes inhibited the oviposition of C. maculatus, indicating that the seed coat was also repellent to insect.     

Amino acid composition,mineral contents and protein solubility of some lima bean (Phaseolus lunatus l. Walp) seeds coat

Seeds coat of four lima beans (Phaseolus lunatus) varieties were subjected to standard analytical techniques in order to evaluate proximate, amino acid, mineral composition and protein solubility. The proximate analysis indicates moisture content in the range of (3.17–4.96%), crude protein (14.53–15.93%), fat (0.62–0.74%), crude fibre (32.59–33.59%), ash (2.43–3.88%), and carbohydrate (47.11–48.62%) on dry weight basis. The most abundant mineral element in the studied seeds coat was potassium 361.20–459.51 mg/100 g followed by sodium 71.27–102.51 mg/100 g and magnesium 83.20–95.23 mg/100 g. Calcium, phosphorus, iron and zinc were also present in significant amount while lead, cobalt and nickel were not detected. The amino acid profile demonstrates nutritionally acceptable results for the samples due to the high levels of essential amino acids in g/100 g protein such as lysine 6.42–7.41, leucine 7.51–8.37, arginine 4.42–7.02 and phenylalanine 5.01–5.49; when compared with FAO/WHO standard; with essential amino acids (TEAA) 49.47–51.07 g/100 g protein. Glutamic and aspartic acid were the most abundant amino acid in all the samples. The protein solubility profiles showed minimum values at pH 4 and more than 70% soluble at pH 10. The study has shown the potentials of lima bean seeds coat, an agro by-products in the development of new functional ingredients for food enrichment to provide an economic alternative raw material for food industries.     

Effect of Dry Heat Pre-Treatment (Toasting) on the Cooking Time of Cowpeas (Vigna unguiculata L. Walp)

Four cowpea varieties (Brown beans, Oloka beans, IAR48 and IT89KD-288) were toasted at 105 °C, and used to study the effect of dry heat treatment on the cooking time and nutrient composition of cowpea seeds and also its effect on the functional properties of resultant flour of the cowpea seed varieties. Toasting reduced the cooking time for brown and oloka cowpea varieties from 55.00–31.00 and 70.67–51.67 min, respectively. The cooking time for IAR48 and IT89KD-288 cowpea varieties increased from 104.67 to 106.00 and 88.00 to 88.67 min, respectively. The results indicate that the cooking time of cowpea seeds can be reduced significantly on toasting, while maintaining their potential as functional agents in the food industry for nutrition and utilisation. Correlation between the amount of water imbibed by cowpea seeds and their cooking time was -0.74, but was not significant at p ≤ 0.05, suggesting that there is no significant relationship between the amount of water imbibed by cowpea seeds and their cooking time.     

Ultrasound-assisted isolation of mucilaginous hydrocolloids from Salvia macrosiphon seeds and studying their functional properties

Time and energy consuming centrifugation and purification steps have been reported as the main challenges for isolation of high quality hydrocolloids from mucilaginous seeds in commercial production. Ultrasound-assisted isolation of mucilaginous hydrocolloids from Salvia macrosiphon seeds as an innovative technology was performed successfully. After determination of optimum swelling condition, mucilaginous hydrocolloids samples were isolated using ultrasonic system under different ultrasound conditions (i.e., time, 1–20 min, temperature, 5–60 °C and ultrasound power (30–150 W)) and their physicochemical characteristics were studied in terms of yield, lightness, chemical composition, rheological properties and intrinsic viscosity in comparison with the conventional method. Ultrasound method increased yield, lightness and purity, in particular protein content, of the isolated hydrocolloids. Rheological measurements showed that increase of the intensity of ultrasound causes a decrease in consistency coefficient and an increase in the flow behavior index and thus hydrocolloid solutions tend to show more Newtonian behavior. The critical concentrations of S. macrosiphon seed gum isolated with the conventional method and the strongest ultrasonic treatment were 0.06 and 0.2 g/dl, respectively. Ultrasound showed to be a suitable method to isolate hydrocolloids from S. macrosiphon seeds.Industrial relevanceIsolation of mucilaginous hydrocolloids from seeds is a major challenge for commercializing these promising hydrocolloids. Using power ultrasound, isolation of hydrocolloid from S. macrosiphon mucilaginous seeds was performed, successfully. Ultrasound is able to scrape swelled mucilage layers of the seeds layer by layer. In the conventional method during high shear application some parts of the seed cores are crushed that would require extra separation steps such as high speed centrifugation. However, with ultrasound method seed cores are not broken down, therefore no centrifugation step is needed.     

Inactivation of Salmonella and Escherichia coli O157:H7 on artificially contaminated alfalfa seeds using high hydrostatic pressure

Alfalfa sprouts contaminated with Salmonella and Escherichia coli O157:H7 have been implicated in several outbreaks of foodborne illnesses in recent years. The seed used for sprouting appears to be the primary source of pathogens. Seed decontamination prior to sprouting presents a unique challenge for the sprouting industry since cells of the pathogenic survivors although undetectable after sanitizing treatments, can potentially multiply back to hazardous levels. The focus of this study was to therefore test the efficacy of high hydrostatic pressure to eliminate a ∼5 log CFU/g load of Salmonella and E. coli O157:H7 on alfalfa seeds. Pressure treatment of 600 MPa for up to 25 min at 20 °C could not result in complete inactivation of Salmonella. High-pressure treatment was then carried out either at sub-ambient (4 °C) or elevated (40, 45 and 50 °C) temperatures to test the ability of high pressure to eliminate Salmonella. Pressure treatment at 4 and 20 °C did not deliver any satisfactory inactivation of Salmonella while high pressure at elevated temperatures achieved complete kill. Pre-soaking seeds prior to high-pressure treatment also enhanced pressure inactivation of Salmonella but at the expense of seed viability. High-pressure treatment of 500 MPa for 2 min at 45 °C was able to eliminate wild-type Salmonella and E. coli O157:H7 strains without bringing about any appreciable decrease in the seed viability.     

Suitability of Protein-Rich Extract from Okra Seed for Formulation of Ready to Use Therapeutic Foods (RUTF)

Protein-rich extract (PRE) was made from okra (Abelmuscus esculentus) seeds. Three versions of feed A, B, and C were formulated using: as sources of protein, A – protein-rich extract from okra seed, B – dehulled and de-fatted okra seed flour (34% protein), C – casein. Each of the feeds was fed to a group of six rats (21 days old mice) for 21 days. The weights of the rats and their droppings were taken at 3-day intervals so were the weights of feed consumed. After 21 days, the rats were decapitated and blood samples harvested. The blood was used for the haematological tests. Liver and heart toxicity indicator including aspartate amino transferase (AST) and alanine amino transferase (ALT) were assayed. Ready-to-use therapeutic food (RUTF) prepared with PRE of okra seeds was formulated and organoleptically assessed in comparison to a standard product. The results showed protein efficiency ratio for A, B, C to be 0.33, 0.14 and 0.47 respectively. The mean weights of the droppings are 2.6, 1.9 and 1.5 respectively, showing significant difference (p ≤ 0.01). The serum AST was 56.5, 72 and 24 (IU/L) respectively. For ALT it was 16.5, 3.1 and 11 respectively. There was no significant difference between the RUTF as well as weaning foods formulated and the standards in terms of overall acceptability (p ≤ 0.01).     

Hyperbaric storage of egg white at room temperature: Effects on hygienic properties,protein structure and technological functionality

Fresh hen (Gallus gallus domesticus) egg white was submitted to hyperbaric storage at 200 MPa at room temperature for up to 28 days. Control samples were stored at 4 °C and 0.1 MPa. Storage conditions were compared for antimicrobial capacity towards inoculated (circa 4 log CFU g⁻¹) Staphylococcus aureus and Salmonella enterica, and changes in physical, structural and functional properties. S. enterica was completely inactivated within 3 h of hyperbaric storage. Prolonged hyperbaric storage promoted slight egg white yellowing, probably due to non-enzymatic browning or riboflavin-protein decomplexation, and induced minor changes in egg white protein structure. Partial conversion of ovalbumin into S-ovalbumin led to slightly decreased gelling capacity. Pressurized egg white proteins also resulted slightly compressed and electrically stabilized, becoming more prone to solvent interactions. Based on these effects, viscosity of egg white increased almost 4-fold and foaming capacity increased by circa 35%. Our work demonstrated for the first time that hyperbaric storage guarantees safety and hygiene of egg white without detriment to its technological functionality.Industrial relevanceHyperbaric storage could represent an interesting alternative to refrigeration due to its capability to preserve food hygienic properties. Concomitantly, it could be used to pasteurize and even enhance technological functionality of protein-rich food ingredients. These goals could be achieved with negligible energetic consumption if working units were made viable for industrial application.